Hoist type pump



J. L. MAULDIN HOIST TYPE PUMP May 1, 1945.

2 Sheets-Sheet 1 Filed June 30, 1942 J. MAULDIN HOIST TYPE PUMP May 1, 1945.

2 Sheets-Sheet 2 Filed June 50, 1942 \\\\\\\\\\I\IlIIIIIIIII/I/I/// Patented May 1, 1945 UNITED, STATES' PATENT A orrlcs nols'r TYPE PUMP John L. Mauldin, Houston, Tex. ApplicationJune 30, 1942, SerialNo. 449,056

3 Claims.

The invention relates to a. hoist type of pump as distinguished from other mechanisms for applying the power to the pump. I

In the drilling of wells by the rotary method a drill stem is rotated in the well bore and a drilling mud is circulated through the drill stem- After the drilling is completed, it is usual to apply a cement mixture either in cementing the casing or in blocking oif various formations.

VVhile in other instances it is desirable to apply various acids to the formation either for the purpose of dissolving the formation or for creating solids to block off the formation.

There are other instances where high pressures are required in the well during the drilling and producing stages of the well, Very often the volume of fluid or liquid to be applied is rather small, but this small volume must be applied under relatively high pressure. The present practice is to engage high pressure pumps which are mounted upon trucks, and it is necessary to bring the truck to the well location in order to force liquid into the well under high pressure. The present invention therefore directs itself to a small volume pump by which high pressures may be obtained while utilizing the hoisting equipment which is present on the drilling rig Fig. 2 is a vertical section of the lower portion of the hoist type pump. 3 H

Fig. 3 is a side elevationwithcertain parts shown in section illustrating. the arrangement [and assembly of the pump as it is connected to .ing or supporting a string of drill pipe3. While and used in hoisting the pipe into and out of the well.

It is one of the objects of the invention to provide a hoist type of pump to be connected to the drill stem or other string of pipe in the well bore so as to force liquid under high pressure into the well.

Another object of the invention is to provide a hoist type of pump where the hoist of the drilling equipment can be utilized to actuate the pu p. i

Another object of the invention is to utilize the combination of drill stem and the hoisting equipment on a drilling rig in order to actuate the pump.

Another object of the invention is to provide a drill stem sub which will act as an anchor for a hoist type pump.

4 Another and further object of the invention is 4 to provide a safety release for the pressure of a hoisttype pump.

Another object of the invention enables the driller to blow plugs out of plugged bits, to test the casing for leaks, to test the casing seat for leakage, and to obtain returns on stuck casing or drill pipe.

Other and further objects of the invention will be readily apparent when the following descripe tion'is considered in connection with the ac companying drawings wherein:

end of'a hoist type pump.

in response to pressure across it.

drill pipe is mentioned, it is to beioistinctly understood that the pumpmay be utilized in connection with any string of pipe disposed in the well bore andto which the pump may be connected. A drill pipe is speciallydescribed because a majorityof the. acts of operation are conducted while the drill pipe is in the well bore. The hoist equipment, illustrated generally at- 4 includes the 1 traveling block 5; the hoisting cable It, the c-hook I and the elevator 8, all of which is standard equipment.

The pump it! is: shown assembled .inzEig; 3 and includes. the housing. H which. is in the form of a hollow cylindrical member 13 having a pump chamber H therein. The lower end of this-housing carries a stuiiing-box 15- which form a seal about the stem or mandrel [-6. This mandrel is hollow and has a central passage ll therein and hasa suitable type of piston 18 mounted on the upper'end thereof and disposed within the chamher [4 in the housing I 2. The housing i2 has an extension 20 thereon in the form of a sleeve carrying an eye or ring .Zln which may be used- Ior'the hoisting operation. This sleeve 20 has a collar 22 so that the elevator 8 maybe clamped about the extension below thecollar in order to effect the hoisting of the housing. I

In order to obtain reciprocation oi the lionsin z z relative to the piston is the lower end of) the mandrel Hi is threaded at-25 into *a sub 26. This: sub is in turn threaded-into the upper end: Of the string of pipe 3 in the well bore as shown at 26 in Fig. 2'.

This sub has a passage 21 therethrough which is in alignment with passage H in the mandrel ii, and which passage continues on into the opening 28in the drill stem or pipe 3. The inlet or entry valve 3!] permits th inflow of fluid through the pipe 31 when there is a reduced pressure in the passages 21' and H, This valve isnormally held closed by a spring 3 2, but opens inwardly An outlet valve 35- controls the discharge from the passage 21 into-drill stem passage 28 and is held closed by a springtfi. Itseems obvious that these two valves 30 and 35 will operate oppo.

sitely of each other so as to control the inlet and outlet of the pump.

The sub 26 may have a pressure gauge 38 mounted thereto so as to show the pressure being applied by the pump in the area below the outlet 3 -valve 35 and it may have a bleed line or control line 39 by which pressure can be introduced or. I

posed in the chamber M has a series of ports il therein so as to connect the pump chamber m with the passage H in the mandrel. a

The piston I8 is of particular construction as seen in Fig. 1 wherein the body 50 is threaded at to the upper end of the mandrel l6 and thus provides a flange 52 upon which the spring 53 is seated. This spring normally urges a set of packing rings 54 against a seat ring 55which is held in position in the lock ring 56.

The piston forms a seal with the inside ofthe housing. The normal weight of the housing will cause the pump to move to the position shown in Figs. 1, 2 and 4, where the housing is in its lowermost position and its downward movement creates a suction in the passages 21 and I6 and in the pump chamber l4 below the piston l8. This reducedpressure serves to draw in a charge of fluid through the pipe 3| and the valve 30 so that-the pump chamber I4 is now charged with fluid.

The hoisting mechanism 4 isnow actuated to raise the housing so that the stufiing'box l5 slides upwardly along the mandrel H5. The usual hoisting equipment on a large rig may be capable of. exerting a tremendous pull, po's'sibly as much as 300,000 lbs., depending'upon how the cable has been reeved and of course, the size and power of the rig. 1 i 1 The weight of the drill stem 3 or any suitable anchorage therefor, such as the closing 'of the blowout preventer rams about the pipe, causes the drill stem to remain stationaryand to hold the mandrel l6 and the piston 18 against upward movement. The fluid in the pump chamber I l below the piston is thus subjected to a tremendous pressure and will be forced backwardly through the ports 4| and the passages ll and 21 was to When the pressure created by the pump exerts the pressure at which the valve 60 has been set to open, it seems obvious that this valve will open and release any pressure inside of: the pump or the drill'string through the Vent in the upper end of the housing in the pump chamber above vthe piston Ill. The escape port 65 may be provided in the top of the extension 20 so as to allow any excess of fluid to escape.

A particular advantage of the pumpis that it may be kept handy at the rig and applied instantly to apply a high pressure to kill the well if it starts to blow out. No other pump capable of such operation or application and constructed of as few and simple parts is known.

Broadly, the invention contemplates a hoist type of pump which can be' utilized with the hoisting equipment on a drilling rig to apply pressure to a string of pipe in the well bore.

What is claimedis: I

1; A drill pipe pump to force a low volume of liquid at high pressure into the drill pipe in position'in a well comprising, a drill pipe, a sub connected to the drill pipe, an inlet valve in said sub to open to admit liquid due to a suction in the sub,-

a hollow stem on said sub, a piston onsaid-stem, an opening in the stem below said piston, a cylinder disposed about said piston and reciprocable on said stem, said piston forming a chamber in the cylinder belowthe piston so as to create a' suction in said chamber to open said inlet valve and draw in a charge of liquid through said sub and stem as said housing is moved down, angoutcause opening of the yal've 35 and the flow of the fluid into the drill pipe28. The pressure which can be applied will of course depend on the pull of the hoisting equipment applied to the exposed area of the piston but it seems obvious that a pressure of many thousands of pounds per square inch can be applied to the well.

It seems clear that reciprocation of thispump will effect a step by step flow of fluid into the drill stem to obtain any desired pressure which may for any other purpose desired. The length of the housing or working barrel will besuch as to obtain the desired length of stroke and volume desired depending on the operation to be performed.

In view of the fact thatvery high pressures are being applied to pipe sections and that such high pressures are exceptionally dangerous, a safety mechanism has been provided in the form of a .release valve 60 which is disposed in a' chamber in the body 50 and normally retained in closed position by a spring 6|, the tension of which may be adjusted by the screw 62. This screw can be "locked in position by a nut 63.

let valvein said sub leading into said drill pipe so as to discharge liquid from said chamber and stem as said cylinder ismoved upwardly, and hoisting means connected to said cylinder to raise the cylinder and discharge the liquid from the cylinder through said'stem and sub into the drill pipe.

y 2. A hoist type of pump for applying pressure in a well including, a drill pipe sub to be threaded to a string of pipe disposed in a well bore, inlet and outlet valves on said sub, a hollow mandrel connected to the top of said sub, a piston on said mandrel, a pump housing reciprocable about said piston, a port in said mandrel below said piston and in said housing to draw in a charge of fluid through said inlet valve and mandrel into the housing through said opening when said housing is moved down around said piston, and to discharge such fiuid through said opening, mandrel, outlet valve, and sub as said housing is raised relative to said piston, and means to raise said housing relative to said sub, mandrel and piston to eiiect such pumping action.

3. A hoist type of pump including a drill pipe sub to be threaded to a string of pipe'disp osed in a well bore, inlet and outlet valves on'said sub, a hollow mandrel connected to the top of said sub,,a piston on said mandrel, a pump housing reciprocable about said piston, a chamber formed in said housing below said piston to receive a charge of fluid through said sub and mandrel due to suction created in the chamber when said housing is'moved down around said piston and to thereafter discharge such fluid through said mandrel and sub as said housing is raised, means to raise said housing relative to said sub, mandrel and piston to effect such discharge, and still additional means carried by said'piston to release pressure created in said chamber which is in ex- JOHN L. MAULDIN, 

